Fields Nguyen 
According to the law of conservation of energy, Energy is neither created nor destroyed, it is only converted from one form to another or from one object to another. And in cars, or other means of transport, when the car is going fast, you step on the brake to stop the car. The kinetic energy of the vehicle is converted into heat. And then all this energy will disappear when your car stops. Do you feel wasteful? If this kinetic energy can be recovered for use, that would be great. And thus, the kinetic energy recovery system was born.
What is Kinetic Energy Recovery System?
The Kinetic Energy Recovery System (KERS) is a system that recovers the kinetic energy of a moving vehicle during braking. This recovered energy is converted and stored in an energy storage system (such as a flywheel or high voltage battery) for later use during acceleration.
According to the above definition, a kinetic energy recovery system is similar to a regenerative braking system. And rightly so, its essence is the same. All work on the principle of taking advantage of existing energy, converting and storing this energy when braking to avoid waste and use later.
Types of KERS
Basically, there are two types of kinetic energy recovery systems, including: Mechanical kinetic energy recovery systems, and electrical kinetic energy recovery systems.
Mechanical energy recovery system
It works on the simple principle of using the inertia force of the flywheel. When the brake is applied, all the kinetic energy of the vehicle will be converted to rotate the flywheel, thanks to this inertia force, the flywheel will rotate at a high speed even when the vehicle is stopped. As soon as the driver releases the brake and steps on the accelerator, the energy from the flywheel will be coupled to transmit force to the wheel, helping the car accelerate better, reducing fuel consumption.
Electric kinetic energy recovery system
It works on the principle of regenerative braking system. The basic system will include a alternator (motor) and a storage battery. Call it alternator/motor because it will switch functions depending on whether you step on the brake or on the gas. When the driver brakes the bike, the kinetic energy of the vehicle will be converted into electricity by the generator and charged into the storage battery. When you release the brake and step on the accelerator, energy from the battery is transferred to the electric motor to support better acceleration.
For the electric system, there may be an option to use it from the driver without requiring immediate use like the mechanical system, because electricity is stored for a long time in the battery.
Applications
The kinetic energy recovery system is known to be most commonly used in Formula I racing cars. However, many other automakers have used it in their commercial vehicles, including Volvo.
With an electric kinetic energy recovery system, its popular application is in the form of regenerative braking. And it is applied almost entirely on electric and hybrid vehicles today.
